Internal-combustion heater burner and ignition means therefor



Sept. 13, 1949.

v. N. TRAMONTINI 2,481,631 INTERNAL-COMBUSTION HEATER BURNER ANDIGNITION MEANS THEREFOR Filed Au 17, 1946 2 Sheets-Sheet 1 0121/21),dfiy dial/megs.

Sept. 13, 1949. v. N. TRAMONTlNl 2,481,631

INTERNAL-COMBUSTION HEATER BURNER AND IGNITION MEANS THEREFOR Filed Aug.17, 1946 2 Sheets-Sheet 2 [lave/$60 1 ems, 1a, 1949 UNITEDINTERNAL-COMBUSTION HEATER BURNER AND IGNITION MEANS THEREFOR Vernonn.Tralnontini, Indianapolis, Inc, .8- signor' to Stewart-WarnerCorporation, Chiu lit. a corporation of Virginia Application August 17,1946, Serial No. 691,190

- 3' Claims. (01. 15 8-28) The present invention relates to heaters andmore particularly to a small size, high output heater for automobilesand other vehicles.

The heater oi the present invention is intended for operation withgasoline or similar liquid lrvdrocarboris as the fuel and may beconsidered as an improvement over the heater forming the subiectmatterotthepresentassigneescopendingapplication of George W. Allen andVernon N. Tramontini for "Heater" flled June 14, 1946 and which has beengiven Serial No. 676,776; Because of the similarities of the twoheaters, reference is made to this copending patent application for amore detailed disclosure of the common subject matter. In general, thetwo heaters are similar excepting forthe burners and certain of thecontrol equipment. The improved burner and equipment directly operatedtherefrom and attached thereto forms the subject matter of the presentinvention.

It is an object of the present invention to pro- ,vide a novelautomobile or similar type combustion heater having improved startingcharacteristics, particularly when flooded or when hot, withoutsacrificing other desirable characteristics, such as the ability tostart in extremely cold weather.

Another object is to provide a novel heater having an improved ignitercontrol arrangement formed in conjunction with the burner.

Yet another object of the present invention is to provide an improvedheater and burner therefor having the above characteristics togetherwith good performance over a wide range of heat output, so that theheater is well adapted for quickly bringing the temperature within anautomobile to a comfortable level even in extremely cold weather whilealso having the ability to operate eiliciently at a very low rate ofheat output, such as may be desired for maintaining the temperaturewithin the vehicle only slightly above ambient in mild weather.

Still another object of the present invention is to provide an improvedautomobile or similar type heater which may be manufactured at low costand which has desirable control characteristics.

Yet another object of the present invention is to provide a novel heaterhaving the above advantages and which has good life characteristics andrequires aminimum of attention in service.

Other objects and advantages will become apparent from the followingdescription of a preterred embodiment of my invention which isillustrated in the accompanying drawings.

In the drawing in which similar characters of 2 reference refer .tosimilar parts throughout the several views:

.Fig. 1 is a sideview of a heater embodying the present invention with aportion thereof broken swag to show the burner in longitudinal medialsec on;

Fig. 2 end view 0! the burner end of the heater; Fig. 8 is a verticaltransverse sectional view through a portion of the burner and may becon-' sidered as taken in the direction of the arrows substantiallyalong the line 8-3 of Fig. 1;

Fig. 4 is a vertical transverse sectional view through a portion of theheater illustrating primarily the construction of an igniter switch forautomatically tuning the heater igniter oil after combustion has beenwell sd and the association of the switch with the burner. This view maybe considered as taken in the direction of the arrows substantiallyalong the line t-d of Fig. 1;

Fig. 5 is a top view of the switch illustrated in Fig. 4; and

Fig. 6 is a vertical transverse sectional view through a portion of theburner and may be con-=- sidered as taken in the direction of the arrowssubstantially along the line ii- 3 of Fig. l.

The heater 0? the present invention comprises a cylindrical casing itthrough which air to be heated is passed, usually from left to right asseen in Fig. 1. For the purpose of making ventilating air ductconnections, a fiange i2 is shown at the left-hand end of the heater inFigl l and may, of

course, also be used at the opposite end or other means may be used asdesired. Air to be heated lated therethrough by means of a scooplocatedin the exterior air stream, such scoops usually being attached tothe fuselage or formed in the lead ing edge of the airplane wing.

Within the casing I ii the air to be heated passes around and through aheat exchanger it which may be of any suitable construction, but for thepresent purpose will be assumed to be of the type more fully describedin the previously referred to copending application. heated a burner It,to be described in greater detail presently, supplies hot products ofcombustion to the space within an inner cy Inthistim shell II.. Thisshell is, therefore, heated and the hot products of combustion passtherefrom through a longitudinally extending sloth not shown, into anouter annular space formed between an outer shell 22 and an intermediateshell 24. .The hot products of combustion in this space therefore heatthe shells 22 and 24 and thereafter pass from the heater throughanexhaust fitting 26 located adjacent the lower side of the heater andopposite the previously referred to slot. The fitting 26 is connected tothe space 26 by way of an opening through the outer shell 22.Ventilating air to be heated passes longitudinally through the annularspace between the casing i8 and the outer shell 22 and alsolongitudinally through the substantially annular pass sage l4.

The burner I6 is formed of sheet metal of an alloy having goodresistance to corrosion at high temperature. Certain of the stainlesssteel alloys are suitable for this purpose and are preferably used forforming the burner l8 and the three cylindrical shells I8, 22 and 24.

The burner I8 is former as a frustum of a cone and is so arranged withinthe heat exchanger that the smaller end 28 thereof is open and serves asthe outlet for the products of combustion. The side wall or conicalsurface 38 of the burner extends toward the adjacent end of the heaterand has a progressively increasing diameter and at its opposite end isclosed by a back plate 32 which is substantially in the plane of theinlet end of the heat exchanger.

Air for combustion is supplied to the burner by a centrifugal blower 34driven by a small electric motor 36, air being drawn inwardly at I anopening 38 to a blower impeller 48 which forces the air outwardly andthrough an outlet 42 connected to a combustion air tube 44. This tubeconnects adjacent the surface of the heater by means of a fitting 46with a similar air tube 48 located within the heater and which passesinwardly to a position within the inner shell 18 where it is curved soas to extend into the open end of the burner. Within the burner the tube48 is connected to an elbow 68 which directs the air downwardly andtangentially in such manner as to cause it to follow a circular pathinside the burner shell and against the back wall 82. In order toconfine the air against the back wall for a portion of a revolution, asemicircular baflle plate 52 extends from the elbow fitting 60 to thelower surface of the burner where it is secured by resistance welding orby any other suitable means. The baille 52 is arrangedin a verticalplane and extends from side to side of the burner from approximately thecenter of the burner downwardly.

The back plate 32 of the burner is provided with a generally rectangularopening 54 in the lower portion thereof, this opening being closed by asheet metal cup or pocket-forming member 56 with its open end 58 fittedto the opening 54, the back plate 32 and contiguous edge of the cup 66being sealed together by welding,

For convenience in reference, the closed end wallof the pocket formingmember 56 is indicated by the numeral 58. The lower surface or floor 60of the pocket slopes generally downwardly from the rear wall 58 to theopening 64 so that, as will be described presently, any gasolineentering the pocket will flow downwardly into the conical shell 38 ofthe burner. In other words, the downwardly sloping floor of the pocket68 causes gasoline to now forwardly while the rearwardly sloping wall 36ofthe burner. being pitched in the opposite direction, causes the liquidfuel to be concentrated in the triangularly shaped zone at the juncturebetween the back wall 82 and the edge of the conical surface 36. Thepitch of both the surfaces 80 and 86 is suiliclent to cause the liquidfuel to be collected as above described regardless of whether thevehicle is operating upon a level surface or whether it is climbing ordescending hills.

With the liquid fuel in this location his in direct contact with theswirling air flowing from the fitting 50. Thus, the fuel and air arerapidly and easily mixed to provide efllcient combustion. Thi mixing ispromoted by passing the air tube 48 for a short distance tl'. ough thezone occupied by the hot products of combustion so that the combustionair is preheated before entering the burner.

At its closed end 58, the pocket 56 is provided with a fitting 62 weldedor brazed thereto which has a threaded opening 64 to receive thethreaded head portion of an igniter 66. The igniter 66 is of the hotwire type and comprises a small diameter cylindrically wound gloosecoil68 located coaxially within a shell 18. Preferably the coil is formed ofNichrome or'similar high temperature resistance wire and has its outerend secured to the end of the shell 10 in any suitable manner, such asby staking in place and then brazing the joint thus formed. The oppositeend of the coil 68 is similarly secured, that is, by brazing or thelike, to the head of a screw 12 which passes through the head of theigniter body 66. In order to prevent electrical contact between thescrew I2 and the body of the igniter,

I the portion of the screw 12 passing through the igniter body isinsulated by a bushing of ceramic or similar material. The screw 12serves as one terminal for the igniter and is secured by nuts 14 to anelectric lead I6, the other terminal of the igniter being grounded.

In order to provide better starting characteristics the igniter shell 18has a row of perforations 18 in the side wall thereof to facilitate theflow of fuel and air mixture around the igniter coil as will bedescribed in greater detail presently. The igniter shell 18 is enclosedcoaxially within a larger cylindrical sleeve 88, the rearward end ofwhich is secured by brazing or the like to the previously mentionedfitting 62, the opposite end of the shell 86 projecting somewhat beyondthe end of the igniter shell 10. So as to provide proper air flowcharacteristics 'within the pocket 56 and to prevent excessiveturbulence a pair of vertical longitudinally extending baffles 82 and 84are arranged below and above the sleeve 8ll'respectively. The lowerbaflie 82 extends from the sleeve 88 to the bottom of the pocket 56 atapproximately the center line of the sleeve and pocket while the upperbaflle 84 extends from the sleeve to the upper surface of the pocket inalignment with the lower baffle 82. These two baflles prevent the rapidrotational flow of air within the conical chamber 30 from causingexcessive turbulence within the rearward portion of the pocket 56.

The fitting 62 is formed to provide a vertical passage 86 open at thetop which communicates with a fuel tube 88 extending to the top of theheater and which is there connected to a fuel control valve 80. Thisvalve may be of the simple on-oil' type and it may also provide high andlow positions. The particular valve forms no part of the presentinvention, but a suitable valve for this purpose is described in thepresent assignees eopending patent application of George W. Allen. filedMay 4, 1948, for "Control Valves" and which has been given Serial No.667,395. The fuel tube has an internal diameter of approximately aquarter-of an inch or so and contains a wick 02 formed of heat andcorrosion resistant material, l'br this purpose I have found that a wickformed of braided stainless steel wire is well suited. This wick extendsfor a considerable distance up into the tube. as at its {upper end,while the lower end passes through an opening in the upper rear cornerof the sheet metal cup forming the chamber 00, so that the lower end ofthe wick projects into the pocket andrests against the upper surface ofthe shell 00. us, gasoline flowing downwardly in the tube 00 to theheater will be absorbed by the wick 02 and will be evenly fed out uponthe surface of the shell 0|.

To-start the heater of the present-invention, the igniter 00 and theblower motor 80 are energiaed, thereby starting the delivery ofcombustion air to the burner and at the same time heating the element 00of the igniter. Simultaneously, the fuel is turned on by energizing thefuel control valve 00 and, if desired, the ventilating air blower, notshown, may be started or, in some systems, starting of the ventilatingair blower may be delayed until the heater reaches a predeterminedtemperature. In any event, so far as ignition is concerned, theimportant considerations are that the igniter be energized, that thefuel be turned on, and that combustion air be supplied to the burner.Under these conditions,

provided with a contact I04. An insulating block of ceramic material I00is fitted over the stud 00 and rests against the upper surface of thestrip I02 and upon its upper surface supports a terminal strip I00formed of mild steel, brass, or the like.

The strip III is also insulated from the stud It by the ceramic bushingI00 and has an eye I I0 formed at its outer end to facilitate solderingto an electrical conductor H2. The opposite end of the strip projectsfrom the bushing I00 in the direction of the contact I04 and is bent sothat its end Ill supports the end of a spring metal strip II! having acontact II! associated with the contact I04. v The strip III lies inface to face relationship with the terminal strip I00 so as toinsuregood electrical contact between these members. Outwardly of the bushingI00 the spring strip II 0 is formed with a loop or S-bend I20 so as toprovide considerable flexibility. By bending the end portion Ill of thesoft metal terminal strip, the contact IIO may be properly located whilethe spring action of the strip I II permits the contact IIB to followthe contact Ill upwardly without unduly stressing either the bimetalstrip I02 or the spring metal strip I I0.

When the heater is cold, the contacts I04 and I I0 are separated withthe strip II8 supported the igniter rapidly reaches ignition temperaturev extremely cold weather and this vapor is mixed with air which findsits way into the pocket, thereby forming a combustible mixture which isin turn ignited by the hot wire element of the igniter 00. Flame,therefore, flashes out into the main burner comprised of the shell andthe back plate 22. Meanwhile, gasoline will have passed over the shell00 and into the bottom of the pocket 08 from which it drains into themain burner in which location it is subjected to the rapidly moving airstream delivered from the fitting 50. The air flowing over the gasolinemixes with the vapor and forms a combustible mixture which is ignited bythe puff of flame from the igniter pocket. Combustion, therefore, isstarted in the main burner and proceeds until extinguished bydeenergizing the valve 00.

Soon after combustion has been started, it is desirable to de-energizethe igniter, both for the purpose of preventing the wastage ofelectrical energy and also because de-energizing the igniter prolongsthe life of this element. The switch for accomplishing this purpose isindicated generally by the numeral 04 and comprises a headed stud 08which projects upwardly through an opening 08 in the upper surface ofthe igniter pocket 00. After this stud has been located as abovedescribed with the head I00 against the inner surface of the top of theigniter pocket, it is secured by resistance welding or by brazing or inany other suitable manner to insure that it will remain fixed and thatno leakage through the opening 00 will take place.

A bimetal strip I02 has an opening therethrough at one end to fit thestud 00 and is positioned with its lower surface over a considerablearea in direct contact with the top surface of the igniter pocket. Thisstrip I02 at its outer end is by the end I of the terminal strip I00.When combustion is initiated in the combustion chamber, the temperatureof the shell 50 will rapidly rise and heat therefore will be conductedfrom the top of the shell to th strip I02, thereby causing it to fiexupwardly until the contacts I 04 and I00 are closed. They remain closeduntil the metal of the combustion chamber has subsequently cooled belowsome predetermined value. The spring metal strip I20 is held in place,along with the terminal strip I00, the bushing I00 and the bimetal stripI02 by a washer I22 formed of insulating material which is clampedagainst the upper surface of the strip I20 by a nut I2l threaded uponthe stud 00.

The switch just described is enclosed within a sheet metal cover I28which slips over the stud 98 and has its lower edge seated around apressed- I out portion I20 of the upper surface of the igniter pocket58. This cover is held in place by a nut I28 threaded to stud and has aslot I30 at one side to permit passage of the terminal strip I00.

Contacts I40 and lit are connected in series with a relay coil and asource of electrical energy,

so that the relay is energized when the contacts are together.Energization of the relay opens a circuit from the electrical energysource to the igniter, thereby allowing the latter to cool aftercombustion has been established.

Having described my invention, what I claim as new and useful, anddesire to secure by Letters Patent of the United States, is:

1. A liquid fuel burner comprising means forming a substantially conicalcombustion chamber disposed upon a horizontal axis and having a closedlarge end and an' open small end, means for admitting combustion airinto said combustion chamber, means forming a pocket communicating withsubstantially the bottom of said combustion chamber through said closedend. anelectrical igniter of the hot wire type horizontally disposedwithin said pocket, a generally cylindrical shell enclosing saidigniter, and means including a wick for delivering liquid fuel againstsaid shell.

2. A liquid fuel burner comprising means forming a combustion chamber,means for admit- 7 tin combustion air into said combustion chamber,means forming a pocket communicating with said combustion chamber, anelectrical igniter of the heated element type disposed within saidpocket, a generally cylindrical shell partially enclosing said igniterand adapted to be heated thereby, and means including a wick in contactwitl-nsaid shell for delivering liquid fuel to said pocket.

3. A liquid fuel burner comprising means iorm=- ing a substantiallyconical combustion chamber having a closed large end and an open smallend, means forming-a combustion air pipe arranged to introducecombustion air tangentially in a transaxial direction into saidcombustion chamher, means forming a small ofiset pocket communicatingwith said combustion chamber through said closed end at the bottomthereof,

an electric igniter of the hot wire type horizontally disposed withinsaid pocket, a generally cylindrical shell partially enclosing saidigniter and disposed to be heated by said igniter, and means including ametallic wick in contact with said shell for delivering all of theliquid fuel required by said combustion chamber to said pocket.

VERNON N. TRAMQNTINI.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNI'I'ED STATES PATENTS

